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Investigating the Cause of Empty Measurement Fields in EVAL3PHISO Kit's STPM005 Software

Associate II

I am attempting to establish a connection between the EVAL3PHISO kit and its accompanying software, the STPM005 GUI. To power up the board, I am utilizing a USB cable connected to my laptop. The illuminated green LED on the kit verifies that the board is receiving power. In order to power up the STPMS2 ICs, I am supplying power from a single-phase source. By connecting the AC phase pins (R-Phase, S-Phase, and T-Phase) and linking the board's neutral to the AC neutral, I ensure that all three phases have the same line voltages, thus powering up all the STPMS2 ICs. I have confirmed this by measuring 3.3V at the STLQ IC using a multimeter, indicating that all ICs are receiving power, Next, I connect to the target by selecting "Target STPM_3PHISO" and choosing the virtual COM port, which is identified as COM15 in my case. Following the guidelines mentioned in the reference manual, I set the baud rate to 115200, data bits to 8, parity to none, stop bit to 1, and flow control to none. These settings allow for a successful connection between the EVAL3PHISO board and the GUI through the USB virtual COM port. The platform type is recognized as PLTF_STM32_Meter. After configuring the settings, when I click the "connect" button on the GUI, the EVAL3PHISO board establishes a successful connection. The terminal displays the message "The board is currently connected to the port \.\COM15" and provides the firmware version, which in my case is '00010002'.

Upon accessing the configuration section, I am presented with a phase selection option. Since I have connected all the phases together to power up all the ICs, I do not connect any loads to the first two shunts. However, I connect my laptop charger as a load to the third shunt, drawing a current between 0.212A and 0.215A. Knowing that my load is connected to the third phase, I select phase 3 in the GUI. A small popup window appears on the screen, and by clicking the "read" button, I can view the default values. I decide to keep the values at their default settings, which are as follows: BHPFC=0, BHPFV=0, CHV [12bit]=2048, CHC [12bit]=2048, and offset configurations OFV [24bit]=4192256 and OFC [24bits]=4192256. I set the other fields to 0. After closing the popup window, I proceed to click the "GET" button for voltage calibration and current calibration. The current and voltage values are displayed. In my case, the line voltages are 237V, and the current is ranging between 0.212A and 0.215A. However, the board returns values of 241252V and 228mA for the current. 

I encounter difficulties when attempting to set values in the input fields for voltage (VRMS) and nominal current (IRMS) in the GUI. Sometimes, the GUI freezes and the software unexpectedly closes, while other times it simply fails to apply any changes. For instance, I input a power factor value of 0.9 to account for the inductive nature of my load, set the voltage factor to 237, and the current factor to 0.200. I also input the same values for voltage calibration (CHV) and current calibration (CHC) to generate appropriate values. Upon clicking the "SET" button, the values should be updated accordingly. However, when I attempt to read the values again, there is no difference. The previous values of 300mA and 245V persist instead of the expected values of 228mA and 240V.

Furthermore, when I navigate to the measurement tab and select the corresponding phase, all fields appear empty, with no values being displayed. I have been stuck on this issue for the past two days. I would greatly appreciate your assistance in identifying the problem. Additionally, I have connected the board with Tera Term for mini shell commands. When I attempt to read the signal register, the values returned are often incorrect. For instance, when I try to read the voltage RMS and current RMS using the address specified on page 8, I use the command "met rd 3 is phase, address 48, and NB is 1" (sometimes 2). However, the data received is completely different from the actual voltage and current values. On the other hand, when I use the command "met metro 6 1 3 2 1" for voltage VRMS and "met metro 6 1 3 1 1" for current, the correct values are obtained, which align with what the GUI displays. When I attempt to read all data by using the command "met metro 21 1 3," no information appears in the Tera Term terminal.

I kindly request your guidance in determining whether the issue lies with the kit or if I am making a mistake in my approach. Thank you for your assistance!